It has been conventionally known to use a computer to perform audio signal processing operations such as recording, editing, mixing, and the like of performance data. The computer is a general purpose computer such as PC (personal computer) and has various hardware devices such as an audio interface and a MIDI (Musical Instrument Digital Interface) I/F, and music software is installed thereon. Application software called DAW (Digital Audio Workstation) is known as conventional music software to be installed on the PC. A PC on which a DAW process is activated functions as a music processing device and is able to execute music processing such as recording/reproducing, editing, and mixing of MIDI data and audio signals.
Functions of the music software of DAW which runs on a PC are plentiful, and installing the music software on a PC enables an individual person to easily create music. On the other hand, functions of the music software has become abundant, and they are complicated to operate when performing all operations of music software (DAW) processes activated on the PC or setting parameters thereof with a mouse or a keyboard of the PC. Accordingly, on advanced scenes of creating music, a physical controller for operating music software processes is connected to the PC on which the music software is installed, and controls such as knobs, sliders, and buttons provided on this physical controller are used to perform operations and setting of parameters when performing recording/reproduction, editing, mixing of performance data and audio data (see PTL1).
Further, there is known a music system in which a plurality of PCs on which the music software is installed are connected to a network, and a controller for controlling respective music software processes activated on the PCs is connected through the network. In this music system, a process (management software process) which manages connection between the controller and a DAW process is activated together with the DAW process on each PC. Then, in response to operation of a switch for switching connection on an operating panel of the controller, the controller switches a music software process to be a subject of the control (see NPL1).